I live in a Mac and PC household, right now it's the Macs (iMac G4 and iBook G4) that have been passed on to the children and an Aldi PC (£350) and a Dell Laptop (£220) that are used by the adults for "work".
I do like Macs - just can't justify the prices at the moment.
Vista is now what OS X was five years ago and it gives me little trouble. My PC does all I need quickly enough for now - I don't bother with Video, so it's just web, office, photos and iTunes.
My wife's low end laptop came with XP as an option and works just fine for email and Open Office.